Learn about the how the Voyager missions are exploring the planet Mars looking for water and the Martian plateaus.
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Learn About the Voyager Missions to Mars Because of Mars low atmospheric pressure and low temperatures, water can’t exist in liquid form. It must either freeze or evaporate. But while there are no oceans or rivers on Mars, there is more water in total that anyone had expected. The residual polar cap in the north which remains after the hardest part of the northern summer is water ice mixed with dust and the measurements of the seasonal behavior of the water vapor over the planet suggest there is a vast reservoir of ice beneath the surface so that one can think of the residual polar cap as the tip of an iceberg protruding from a sea of rock. At lower latitudes, a water vapor condenses the form clouds that ride high in the atmosphere or swirl around the slopes of Martian volcanoes. In further south in the canyons and valleys, there is frequently an ice haze seem form and evaporate in the early hours of the morning as the sun warms the atmosphere. In this model, the flat surface of a large Martian plateau is catch by the Great Rift. A smooth sloping ravine drops abruptly against the bottom of the canyon four miles below. The small peaks on the canyon floor were once part of the plateau surface. Today, this great fracture in the crust of Mars is 75 miles across. The original fault has been widened and shaped by various forms of erosion. Great landslides are triggered by quakes that shake the crustal rocks. Windblown dusts strips the canyon walls, some side canyons may have been deepened by running water. Melting of underground ice followed by slumping of walls further erodes the great fault. This rift valley of which we have early seen a small part is so huge that it would span the United States and the Grand Canyon of Arizona would fit inside one of the smaller tributaries. These are just some of the mysteries of Mars unmapped by the extraordinary voyager missions.